| Device | Input Energy | Useful Output | Efficiency |
|---|---|---|---|
| Incandescent bulb | Electrical | Light | ~5% |
| LED bulb | Electrical | Light | ~40–50% |
| Petrol car engine | Chemical (fuel) | Kinetic | ~25% |
| Electric motor | Electrical | Kinetic | ~90% |
| Solar panel | Light (solar) | Electrical | ~15–22% |
| Human body (walking) | Chemical (food) | Kinetic | ~25% |
This comparison covers Efficiency of Common Devices within Efficiency for GCSE Physics. Revise Efficiency in Energy for GCSE Physics with 19 exam-style questions and 4 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 5 of 13 in this topic. Use this comparison to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Efficiency
Which equation correctly defines efficiency?
Explain one method that can be used to reduce unwanted energy transfers in a machine and state how it reduces waste.
Quick recall flashcards
As a decimal
0.85 (between 0 and 1)
As a percentage
85% (multiply decimal by 100)